<#--

    Symphony - A modern community (forum/BBS/SNS/blog) platform written in Java.
    Copyright (C) 2012-present, b3log.org

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <https://www.gnu.org/licenses/>.

-->
<!DOCTYPE html>
<html lang="zh-cmn-Hans">
<head>
    <meta charset="UTF-8">
    <title>${forwardingLabel} - ${symphonyLabel}</title>
    <meta name="description" content="${forwardingLabel}"/>
    <meta name="robots" content="noindex">
    <link rel="icon" type="image/png" href="${staticServePath}/images/favicon.png"/>
    <link rel="apple-touch-icon" href="${staticServePath}/images/apple-touch-icon.png">
    <link rel="shortcut icon" type="image/x-icon" href="${staticServePath}/images/favicon.png">
    <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=0"/>
    <style>
        html {
            height: 100%;
        }

        body {
            font-family: "Helvetica Neue", "Luxi Sans", "DejaVu Sans", Tahoma, "Hiragino Sans GB", "Microsoft Yahei", sans-serif;
            background: #79a8ae;
            color: #CFEBE4;
            font-size: 18px;
            line-height: 1.6;
            margin: 0;
        }

        a {
            color: #ebf7f4;
        }

        .body--ready {
            background: -webkit-linear-gradient(top, rgb(203, 235, 219) 0%, rgb(55, 148, 192) 120%);
            background: -moz-linear-gradient(top, rgb(203, 235, 219) 0%, rgb(55, 148, 192) 120%);
            background: -o-linear-gradient(top, rgb(203, 235, 219) 0%, rgb(55, 148, 192) 120%);
            background: -ms-linear-gradient(top, rgb(203, 235, 219) 0%, rgb(55, 148, 192) 120%);
            background: linear-gradient(top, rgb(203, 235, 219) 0%, rgb(55, 148, 192) 120%);
            text-align: center;
            display: flex;
            flex-direction: column;
            height: 100%;
            padding-bottom: 20px;
            box-sizing: border-box;
        }

        .text {
            flex: 1;
        }

        button {
            cursor: pointer;
            color: #000;
            border-radius: 3px;
            padding: 6px 12px;
            background-color: hsla(0, 0%, 100%, .58);
            border: 1px solid #d5d5d5;
            border-bottom-color: #e1e1e1;
            box-sizing: border-box;
            line-height: 19px;
            white-space: nowrap;
            display: inline-block;
            font-size: 14px;
            outline: none;
            margin-top: 20px;
        }

        button:hover {
            text-decoration: none;
            border-color: #eee;
            background-color: hsla(0, 0%, 100%, .8);
        }

        button:active,
        button:focus {
            box-shadow: inset 0 2px 15px rgba(0, 0, 0, .25)
        }

        .canvas {
            height: 50vh;
            width: 50vw;
            margin: 0 auto;
            display: block;
        }
    </style>
</head>
<body class="body--ready">
<canvas class="canvas"></canvas>
<div class="text">
    是否跳转至 <a rel="nofollow" href="${forwardURL}">${forwardURL}</a><br/>
    <button onclick="window.location.replace('${forwardURL}')">确定</button>
</div>
<div>
    <a href="https://github.com/88250/symphony">GitHub</a> &nbsp;
    <a href="https://b3log.org/" target="_blank" rel="noopener">B3log</a>
</div>
<script>
    var S = {
        init: function () {
            S.Drawing.init('.canvas')
            document.body.classList.add('body--ready')
            var text = 'Sym'
            S.UI.simulate(text)
            S.Drawing.loop(function () {
                S.Shape.render()
            })
        },
    }

    S.Drawing = (function () {
        var canvas,
                context,
                renderFn,
                requestFrame = window.requestAnimationFrame ||
                        window.webkitRequestAnimationFrame ||
                        window.mozRequestAnimationFrame ||
                        window.oRequestAnimationFrame ||
                        window.msRequestAnimationFrame ||
                        function (callback) {
                            window.setTimeout(callback, 1000 / 60)
                        }

        return {
            init: function (el) {
                canvas = document.querySelector(el)
                context = canvas.getContext('2d')
                this.adjustCanvas()

                window.addEventListener('resize', function (e) {
                    S.Drawing.adjustCanvas()
                })
            },
            loop: function (fn) {
                renderFn = !renderFn ? fn : renderFn
                this.clearFrame()
                renderFn()
                requestFrame.call(window, this.loop.bind(this))
            },
            adjustCanvas: function () {
                canvas.width = window.innerWidth
                canvas.height = window.innerHeight
            },
            clearFrame: function () {
                context.clearRect(0, 0, canvas.width, canvas.height)
            },
            getArea: function () {
                return {w: canvas.width, h: canvas.height}
            },
            drawCircle: function (p, c) {
                context.fillStyle = c.render()
                context.beginPath()
                context.arc(p.x, p.y, p.z, 0, 2 * Math.PI, true)
                context.closePath()
                context.fill()
            },
        }
    }())

    S.UI = (function () {
        var interval,
                currentAction,
                time,
                maxShapeSize = 30,
                sequence = [],
                cmd = '#'

        function formatTime (date) {
            var h = date.getHours(),
                    m = date.getMinutes(),
                    m = m < 10 ? '0' + m : m
            return h + ':' + m
        }

        function getValue (value) {
            return value && value.split(' ')[1]
        }

        function getAction (value) {
            value = value && value.split(' ')[0]
            return value && value[0] === cmd && value.substring(1)
        }

        function timedAction (fn, delay, max, reverse) {
            clearInterval(interval)
            currentAction = reverse ? max : 1
            fn(currentAction)

            if (!max || (!reverse && currentAction < max) || (reverse && currentAction > 0)) {
                interval = setInterval(function () {
                    currentAction = reverse ? currentAction - 1 : currentAction + 1
                    fn(currentAction)

                    if ((!reverse && max && currentAction === max) || (reverse && currentAction === 0)) {
                        clearInterval(interval)
                    }
                }, delay)
            }
        }

        function performAction (value) {
            var action,
                    value,
                    current

            sequence = typeof (value) === 'object' ? value : sequence.concat(value.split('|'))

            timedAction(function (index) {
                current = sequence.shift()
                action = getAction(current)
                value = getValue(current)

                switch (action) {
                    case 'countdown':
                        value = parseInt(value) || 10
                        value = value > 0 ? value : 10

                        timedAction(function (index) {
                            if (index === 0) {
                                if (sequence.length === 0) {
                                    S.Shape.switchShape(S.ShapeBuilder.letter(''))
                                } else {
                                    performAction(sequence)
                                }
                            } else {
                                S.Shape.switchShape(S.ShapeBuilder.letter(index), true)
                            }
                        }, 1000, value, true)
                        break

                    case 'rectangle':
                        value = value && value.split('x')
                        value = (value && value.length === 2) ? value : [maxShapeSize, maxShapeSize / 2]

                        S.Shape.switchShape(S.ShapeBuilder.rectangle(Math.min(maxShapeSize, parseInt(value[0])),
                                Math.min(maxShapeSize, parseInt(value[1]))))
                        break

                    case 'circle':
                        value = parseInt(value) || maxShapeSize
                        value = Math.min(value, maxShapeSize)
                        S.Shape.switchShape(S.ShapeBuilder.circle(value))
                        break

                    case 'time':
                        var t = formatTime(new Date())

                        if (sequence.length > 0) {
                            S.Shape.switchShape(S.ShapeBuilder.letter(t))
                        } else {
                            timedAction(function () {
                                t = formatTime(new Date())
                                if (t !== time) {
                                    time = t
                                    S.Shape.switchShape(S.ShapeBuilder.letter(time))
                                }
                            }, 1000)
                        }
                        break

                    default:
                        S.Shape.switchShape(S.ShapeBuilder.letter(current[0] === cmd ? 'Sym' : current))
                }
            }, 2000, sequence.length)
        }

        return {
            simulate: function (action) {
                performAction(action)
            },
        }
    }())

    S.Point = function (args) {
        this.x = args.x
        this.y = args.y
        this.z = args.z
        this.a = args.a
        this.h = args.h
    }

    S.Color = function (r, g, b, a) {
        this.r = r
        this.g = g
        this.b = b
        this.a = a
    }

    S.Color.prototype = {
        render: function () {
            return 'rgba(' + this.r + ',' + +this.g + ',' + this.b + ',' + this.a + ')'
        },
    }

    S.Dot = function (x, y) {
        this.p = new S.Point({
            x: x,
            y: y,
            z: 5,
            a: 1,
            h: 0,
        })

        this.e = 0.07
        this.s = true

        this.c = new S.Color(255, 255, 255, this.p.a)

        this.t = this.clone()
        this.q = []
    }

    S.Dot.prototype = {
        clone: function () {
            return new S.Point({
                x: this.x,
                y: this.y,
                z: this.z,
                a: this.a,
                h: this.h,
            })
        },
        _draw: function () {
            this.c.a = this.p.a
            S.Drawing.drawCircle(this.p, this.c)
        },
        _moveTowards: function (n) {
            var details = this.distanceTo(n, true),
                    dx = details[0],
                    dy = details[1],
                    d = details[2],
                    e = this.e * d

            if (this.p.h === -1) {
                this.p.x = n.x
                this.p.y = n.y
                return true
            }

            if (d > 1) {
                this.p.x -= ((dx / d) * e)
                this.p.y -= ((dy / d) * e)
            } else {
                if (this.p.h > 0) {
                    this.p.h--
                } else {
                    return true
                }
            }

            return false
        },
        _update: function () {
            if (this._moveTowards(this.t)) {
                var p = this.q.shift()

                if (p) {
                    this.t.x = p.x || this.p.x
                    this.t.y = p.y || this.p.y
                    this.t.z = p.z || this.p.z
                    this.t.a = p.a || this.p.a
                    this.p.h = p.h || 0
                } else {
                    if (this.s) {
                        this.p.x -= Math.sin(Math.random() * 3.142)
                        this.p.y -= Math.sin(Math.random() * 3.142)
                    } else {
                        this.move(new S.Point({
                            x: this.p.x + (Math.random() * 50) - 25,
                            y: this.p.y + (Math.random() * 50) - 25,
                        }))
                    }
                }
            }

            d = this.p.a - this.t.a
            this.p.a = Math.max(0.1, this.p.a - (d * 0.05))
            d = this.p.z - this.t.z
            this.p.z = Math.max(1, this.p.z - (d * 0.05))
        },
        distanceTo: function (n, details) {
            var dx = this.p.x - n.x,
                    dy = this.p.y - n.y,
                    d = Math.sqrt(dx * dx + dy * dy)

            return details ? [dx, dy, d] : d
        },
        move: function (p, avoidStatic) {
            if (!avoidStatic || (avoidStatic && this.distanceTo(p) > 1)) {
                this.q.push(p)
            }
        },
        render: function () {
            this._update()
            this._draw()
        },
    }

    S.ShapeBuilder = (function () {
        var gap = 13,
                shapeCanvas = document.createElement('canvas'),
                shapeContext = shapeCanvas.getContext('2d'),
                fontSize = 500,
                fontFamily = 'Avenir, Helvetica Neue, Helvetica, Arial, sans-serif'

        function fit () {
            shapeCanvas.width = Math.floor(window.innerWidth / gap) * gap
            shapeCanvas.height = Math.floor(window.innerHeight / gap) * gap
            shapeContext.fillStyle = 'red'
            shapeContext.textBaseline = 'middle'
            shapeContext.textAlign = 'center'
        }

        function processCanvas () {
            var pixels = shapeContext.getImageData(0, 0, shapeCanvas.width, shapeCanvas.height).data
            dots = [],
                    pixels,
                    x = 0,
                    y = 0,
                    fx = shapeCanvas.width,
                    fy = shapeCanvas.height,
                    w = 0,
                    h = 0

            for (var p = 0; p < pixels.length; p += (4 * gap)) {
                if (pixels[p + 3] > 0) {
                    dots.push(new S.Point({
                        x: x,
                        y: y,
                    }))

                    w = x > w ? x : w
                    h = y > h ? y : h
                    fx = x < fx ? x : fx
                    fy = y < fy ? y : fy
                }

                x += gap

                if (x >= shapeCanvas.width) {
                    x = 0
                    y += gap
                    p += gap * 4 * shapeCanvas.width
                }
            }

            return {dots: dots, w: w + fx, h: h + fy}
        }

        function setFontSize (s) {
            shapeContext.font = 'bold ' + s + 'px ' + fontFamily
        }

        function isNumber (n) {
            return !isNaN(parseFloat(n)) && isFinite(n)
        }

        function init () {
            fit()
            window.addEventListener('resize', fit)
        }

        // Init
        init()

        return {
            imageFile: function (url, callback) {
                var image = new Image(),
                        a = S.Drawing.getArea()

                image.onload = function () {
                    shapeContext.clearRect(0, 0, shapeCanvas.width, shapeCanvas.height)
                    shapeContext.drawImage(this, 0, 0, a.h * 0.6, a.h * 0.6)
                    callback(processCanvas())
                }

                image.onerror = function () {
                    callback(S.ShapeBuilder.letter('What?'))
                }

                image.src = url
            },
            circle: function (d) {
                var r = Math.max(0, d) / 2
                shapeContext.clearRect(0, 0, shapeCanvas.width, shapeCanvas.height)
                shapeContext.beginPath()
                shapeContext.arc(r * gap, r * gap, r * gap, 0, 2 * Math.PI, false)
                shapeContext.fill()
                shapeContext.closePath()

                return processCanvas()
            },
            letter: function (l) {
                var s = 0

                setFontSize(fontSize)
                s = Math.min(fontSize,
                        (shapeCanvas.width / shapeContext.measureText(l).width) * 0.8 * fontSize,
                        (shapeCanvas.height / fontSize) * (isNumber(l) ? 1 : 0.45) * fontSize)
                setFontSize(s)

                shapeContext.clearRect(0, 0, shapeCanvas.width, shapeCanvas.height)
                shapeContext.fillText(l, shapeCanvas.width / 2, shapeCanvas.height / 2)

                return processCanvas()
            },
            rectangle: function (w, h) {
                var dots = [],
                        width = gap * w,
                        height = gap * h

                for (var y = 0; y < height; y += gap) {
                    for (var x = 0; x < width; x += gap) {
                        dots.push(new S.Point({
                            x: x,
                            y: y,
                        }))
                    }
                }

                return {dots: dots, w: width, h: height}
            },
        }
    }())

    S.Shape = (function () {
        var dots = [],
                width = 0,
                height = 0,
                cx = 0,
                cy = 0

        function compensate () {
            var a = S.Drawing.getArea()

            cx = a.w / 2 - width / 2
            cy = a.h / 2 - height / 2
        }

        return {
            shuffleIdle: function () {
                var a = S.Drawing.getArea()

                for (var d = 0; d < dots.length; d++) {
                    if (!dots[d].s) {
                        dots[d].move({
                            x: Math.random() * a.w,
                            y: Math.random() * a.h,
                        })
                    }
                }
            },
            switchShape: function (n, fast) {
                var size,
                        a = S.Drawing.getArea()

                width = n.w
                height = n.h

                compensate()

                if (n.dots.length > dots.length) {
                    size = n.dots.length - dots.length
                    for (var d = 1; d <= size; d++) {
                        dots.push(new S.Dot(a.w / 2, a.h / 2))
                    }
                }

                var d = 0,
                        i = 0

                while (n.dots.length > 0) {
                    i = Math.floor(Math.random() * n.dots.length)
                    dots[d].e = fast ? 0.25 : (dots[d].s ? 0.14 : 0.11)

                    if (dots[d].s) {
                        dots[d].move(new S.Point({
                            z: Math.random() * 20 + 10,
                            a: Math.random(),
                            h: 18,
                        }))
                    } else {
                        dots[d].move(new S.Point({
                            z: Math.random() * 5 + 5,
                            h: fast ? 18 : 30,
                        }))
                    }

                    dots[d].s = true
                    dots[d].move(new S.Point({
                        x: n.dots[i].x + cx,
                        y: n.dots[i].y + cy,
                        a: 1,
                        z: 5,
                        h: 0,
                    }))

                    n.dots = n.dots.slice(0, i).concat(n.dots.slice(i + 1))
                    d++
                }

                for (var i = d; i < dots.length; i++) {
                    if (dots[i].s) {
                        dots[i].move(new S.Point({
                            z: Math.random() * 20 + 10,
                            a: Math.random(),
                            h: 20,
                        }))

                        dots[i].s = false
                        dots[i].e = 0.04
                        dots[i].move(new S.Point({
                            x: Math.random() * a.w,
                            y: Math.random() * a.h,
                            a: 0.3, //.4
                            z: Math.random() * 4,
                            h: 0,
                        }))
                    }
                }
            },
            render: function () {
                for (var d = 0; d < dots.length; d++) {
                    dots[d].render()
                }
            },
        }
    }())
    S.init()
</script>
</body>
</html>
